The present invention relates to energy conversion (and storage) systems. More particularly, this invention pertains to transformerless systems for converting energy into electric power of a pre-selected character chosen in accordance with a desired application.
It has heretofore been known in the art to generate electrical energy from a variety of non-electrical modes of nature. In fact, many of such methods reflect relatively ancient technologies; others, though of more recent conception, often reflect primitive approaches to age old problems (e.g., efficiency, economy and durability) that are recognized as inherent shortcomings of such systems.
Often energy conversion systems as abovedescribed will utilize a plurality of energy storage means, such as batteries, to store electrical energy which has been derived from a non-electrical source. An example of such a system is disclosed in U.S. Pat. No. 2,148,804 of Claytor for "Electrical System for Wind Driven Generators" which was issued in 1939.
In producing useable electrical energy, it is essential that the ultimate form or character of the electrical energy generated be compatible with the intended ultilization system. For example, 400 cycle per second alternating current is required to drive some of the (utilization) systems employed in airplanes whereas 60 cycle per second alternating current is appropriate for households and direct current for television sets. On the other hand, differing sources of electrical energy are characterized by a variety of output voltage forms when such sources generate electrical energy. For example, while solar panels produce direct current, wind mills generate either direct or alternating current and water wheels generate direct or alternating current. The obvious incompatibilities of particular inputs with certain end uses limits the possibility of efficient utilization of certain natural energy resources, such as wind, sun and running water, whose abundance is often geographically limited, with respect to end uses that tend to be non-regional in character.
Numerous attempts have been made to synthesize or generate utilization waveforms of pre-selected character. Transformers, well-known in the electrical art, often comprise rather bulky plus heavy configurations, including a magnetic core, rendering the transformer suboptimal for certain classes of uses including, of course, those of an airborne character encountered with respect to airplanes, satellites, missiles and the like. Other methods and means for generating or synthesizing pre-selected waveforms are disclosed in U.S. Pat. No. 4,129,817 of Yew et al. for "Step Voltage Power Supply with Equalized Discharge of Battery Cells", U.S. Pat. No. 3,100,851 of Ross et al. for "High Power Synthetic Wave Form Generator", U.S. Pat. No. 3,391,323 of Ikeda for "High Efficiency Synthetic Wave Inverter", U.S. Pat. No. 3,440,514 of Finley for "Static Inverter" and U.S. Pat. No. 3,324,376 of Hunt for "Linear D.C. to A.C. Converter". The foregoing represent various systems and configurations for generating electrical signals of preselected character or form. Systems for charging storage elements such as batteries are disclosed in U.S. Pat. No. 1,534,026 of Burne for "Charging Secondary Batteries" and U.S. Pat. No. 3,928,791 of Mullersman for "Stand-by Power System".
None of the above-referenced systems discloses a fully flexible, efficient, integrated approach to energy conversion.
The present invention overcomes the above-referenced shortcomings of the prior art by providing a fully integrated, flexible, highly efficient and durable energy conversion system. This system includes subsystems for (1) generating electrical energy of a preselected character by means including computer control (2) storing the electrical energy produced by means of a conversion device such as a solar panel, windmill or the like in an optimum distribution among a plurality of storage elements and (3) tapping the electrical energy, in the form of stored electrical charge in a preselected, programmable manner to provide electrical energy of a predetermined character.
In its specific aspects, the present invention includes a system for converting force into electrical energy of a preselected character. To accomplish this end, there is provided a generator for producing electrical energy of a first character in response to the natural force. Charge storage means are utilized that include a plurality of charge storage elements. A first bus of at least one conductor provides an electrical path between the output of the generator and the charge storage means while a second bus of at least one conductor is in electrical connection with the charge storage means. A switching network controls the flow of electrical energy from the first bus to the charge storage elements of the charge storage means and from the charge storage elements to the second bus. A programmable apparatus is provided to control the switching network.
In a further aspect, the invention comprises apparatus for generating electrical waveform(s) of preselected character. The apparatus of this subsystem includes an output port comprising at least one pair of conductors. Means comprising at least one charge storage element, are provided for storing electrical energy. Programmable apparatus is provided for coupling the charge storage elements to the output port in accordance with a preselected programmed sequence so that an electrical waveform of preselected character is produced at the port.
An additional inventive aspect relates to a switching network for controlling the discharging of an array of charge storage elements onto a first bus comprising a first set of conductors and the charging of the elements by current carried on a second bus comprising a second set of conductors in response to control words generated by means of a digital computer. The switching network includes a plurality of conductors to interconnect the charge storage elements and to connect the elements to the sets of conductors. Series closure switches are positioned to regulate electrical coupling between adjacent charge storage elements. Data switches are positioned to regulate the flow of current between charge storage elements and the conductors of the first and second buses. Means are provided for decoding the control word into a plurality of control signals and for transmitting the control signals to the switches.
In a final aspect, the present invention comprises a method for generating an electrical signal having a waveform of preselected character. The method includes, as a first step, arranging a pluality of charge storage elements into a ring-like configuration. A switchable connection is provided between each pair of charge storage elements. A plurality of conductors is arranged as an output port and a switchable connection is provided between each of the switchable connection is provided between each of the charge storage elements and the conductors. The switches are programmably controlled according to a preselected switching sequence so that a preselected sequence of connections is made between the charge storage elements and the conductors. A time delay is programmably associated with each of the connections to provide an electrical signal having a waveform of preselected character at the output port.
The foregoing and additional aspects, features and advantages of the present invention will become evident from the detailed description thereof which follows. This description is accompanied by and provides an index to drawings in which like characters refer to like features of the invention throughout.